I'm implementing a voip application using gstreamer, i use the example of the rtp in the plugin-good! i want to implement echo cancellation, i couldn't use the speex echo canceller with gstreamer because the input and the output are not in the same process. So, i want to use pulse audio to make echo cancellation? can any one help me how to deal with? the sender voice is

pipeline = gst_pipeline_new (NULL);
  g_assert (pipeline);

  /* the audio capture and format conversion */
  audiosrc = gst_element_factory_make (pulsesrc, "audiosrc");
  g_assert (audiosrc);
  audioconv = gst_element_factory_make ("audioconvert", "audioconv");
  g_assert (audioconv);
  audiores = gst_element_factory_make ("audioresample", "audiores");
  g_assert (audiores);
  /* the encoding and payloading */
  audioenc = gst_element_factory_make (AUDIO_ENC, "audioenc");
  g_assert (audioenc);
  audiopay = gst_element_factory_make (AUDIO_PAY, "audiopay");
  g_assert (audiopay);

  /* add capture and payloading to the pipeline and link */
  gst_bin_add_many (GST_BIN (pipeline), audiosrc, audioconv, audiores,
      audioenc, audiopay, NULL);

  if (!gst_element_link_many (audiosrc, audioconv, audiores, audioenc,
          audiopay, NULL)) {
    g_error ("Failed to link audiosrc, audioconv, audioresample, "
        "audio encoder and audio payloader");
  }

and the receiver is :

gst_bin_add_many (GST_BIN (pipeline), rtpsrc, rtcpsrc, rtcpsink, NULL);

  /* the depayloading and decoding */
  audiodepay = gst_element_factory_make (AUDIO_DEPAY, "audiodepay");
  g_assert (audiodepay);
  audiodec = gst_element_factory_make (AUDIO_DEC, "audiodec");
  g_assert (audiodec);
  /* the audio playback and format conversion */
  audioconv = gst_element_factory_make ("audioconvert", "audioconv");
  g_assert (audioconv);
  audiores = gst_element_factory_make ("audioresample", "audiores");
  g_assert (audiores);
  audiosink = gst_element_factory_make (pulsesink, "audiosink");
  g_assert (audiosink);

  /* add depayloading and playback to the pipeline and link */
  gst_bin_add_many (GST_BIN (pipeline), audiodepay, audiodec, audioconv,
      audiores, audiosink, NULL);

  res = gst_element_link_many (audiodepay, audiodec, audioconv, audiores,
      audiosink, NULL);
  g_assert (res == TRUE);

i tried to change gstreamer proprietes to pulseaudio server in input and output and i used "pactl load-module module-echo-cancel aec_method=adrian" but i still listen to echo!! any one could help please thanks!!